Fuse



Feb. 6, 1934. E. ADAMS ET AL FUSE Filed March 18, 1932 Patented Feb. 6, 1934 UNITED STATES PATENT OFFICE FUSE Ervin Adams, Everett, and Samuel W. Blakslee, Pottsville, Pa.

This invention relates to fuse means for pro-- tecting electrical appliances.

An object of the present invention is to provide a device having a plurality of fuses of suiiicient capacity to protect the particular appliances in use, the fuse casing having a plurality of separate compartments housing individual fuses adapted to be brought into the circuit in sequence to replace burned out fuses by simply rotating the casing axially.

A further object is to provide a fuse casing of cylindrical shape adapted to be rotatably mounted on its axis in spring clips carried by the plug base, in combination with a post also -carried by the base and performing the dual function of facilitating application of the fuse casing to the clips, and forming a stop to limit rotation of the casing in the clips to accurately position the fuses in the circuit.

A further object is to provide a continuous housing for the fuse casing to reduce fire hazard, the housing being separable to permit replacement of the fuse casing when the fuses are all blown by simply unscrewing a shell from a threaded base which carries the spring clips.

With the above and other objects in View the invention consists in certain novel details of construction and combinations of parts hereinafter fully described and claimed it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawing forming part of 5 this specification,

Figure 1 is a longitudinal sectionof a plug embodying the invention.

Figure 2 is an enlarged section through the fuse casing and its mountings taken on the line 22 Of Figure 3,

Figure 3 is a cross section taken on the line 33 of Figure 2,

Figure 4 is a perspective view of the fuse casing, and

5 Figure 5 is a perspective view of one of the attaching prongs.

Referring to the drawing in which like characters of reference designate similar parts in the various views, the device is shown to comprise a disk base 10 having threads 11, and preferably formed of insulating material. The base is provided with spring prongs 12, which have the upper terminals bent outwardly and countersunk in the inner face of the base. Screws 13 are passed through said terminals and into the base for securing the prongs in place. The free ends of the prongs are provided with bosses 14 to prevent dislodgment of the prongs from the usual Wall socket or other fixture.

The base is screwed into a ring 15 having threads 16, and having an integral radial wall 17, and a dome shaped shell 18, all preferably formed of insulating material. An opening 19 is formed in the shell to receive the cord 20 which carries the circuit wires 21.

On the base we provide a pair of spring metal clips 22, the lower ends 23 of which are disposed substantially parallel and are bent outwardly at the terminals to provide feet 24, one of which is superposed upon the bent terminal of one of the prongs 12, and is secured in good electrical contact with the latter by means of the above mentioned securing screw 13 thereof. The foot of the other clip is embedded in the inner face of the base and is secured in place by a screw 25. The clips are bowed outwardly intermediate the ends, and the free ends of both clips are curved outwardly to provide guide lips 26 for facilitating application of the fuse casing 27 to the clips. The spring clips are connected in series with the conductor wires 21, as best shown in Figure 1, one of the wires being connected to the screw 25, as best shown in Figure 2, while the other wire is connected to the screw 13 of the prong 12 disposed remote from the spring clips, as shown in Figure 1.

The cylindrical fuse casing 27 is open at both ends and is provided centrally with a division wall 28, as shown in Figure 3, and preferably is formed of insulating material. A pair of closures, preferably transparent windows 29, formed of any suitable material, close the open ends of the casing, each window preferably having a circumferential flange 30 which is sprung into a recess 31 formed in the inner wall of the casing and lodges against a retaining shoulder 32 which retains the window in place.

A fuse 33 is arranged in each of the two end compartments formed in the casing by the division wall 28. Each fuse terminates in transverse heads 34 which are countersunk in the circumferential face of the casing and are adapted to contact with the spring clips 22. The fuses 33 are arranged in planes intersecting each other at a right angle, as best shown in Figures 2 and 3. Thus the heads 34 are spaced around the circumferential face of the casing about or a quadrant of a circle, apart.

A post 35 is preferably formed integral with the screw base 10 and extends midway between the spring clips 23. The tip of the post is rounded, as shown at 36, and is receivable in de pressions 37 formed in the circumferential face of the casing near the heads 34 of the fuses. These depressions 37 are preferably arranged in an annular series in a single plane, as best shown in Figure 4, so that when the casing is rotated on its axis the tip of the post 35 will lodge in one of the depressions and anchor the casing accurately in position to dispose the heads 34 of that fuse 90 in advance of said depression,

in good electrical contact with both spring clips 22, as best shown in Figure 2.

It will be understood that the spring clips 22 exert sufficient friction against opposite sides of the casing 27 to hold the casing stationary against accidental rotation after the post 35 has lodged in one of the depressions 37.

It will be pointed out that the post 35 limits insertion of the fuse casing 27 between the spring clips 22 so that the casing can at no time be shoved so far between the clips as to damage the clips by spreading them too far apart or dislodge them from their securing screws 13 and 25.

In operation, when one of the fuses 33 has been blown, it is simply necessary to unscrew the shell 18 from the base 10 and manually rotate the fuse casing 27 through an arc of 90. This operation removes the heads 34 of the burned out fuse from contact with the spring clips 22 and positions the heads 34 of the unused fuse in contact with the spring clips. The post 35 lodges in a corresponding depression 3'? in the casing to limit such rotary movement and prop- 35 erly positions the heads of the unused fuse to engage both spring clips.

It will further be observed that when the base 10 is screwed into the ring 15 the shell 18 completely houses the fuse casing so that when a fuse blows no fire hazard can result.

From the above description it is thought that the construction and operation of the invention will be fully understood without further explanation.

What is claimed is:

1. In combination, spring clips, a fuse casing embraced and frictionally seated by the clips and adapted to be raised and rotated on its axis between the clips, a plurality of fuses carried by the casing insulated from each other, the ends of the fuses being exposed on the peripheral face of the casing, the ends of one fuse being located between the ends of the other fuse, and means for limiting rotation of the casing to dispose the ends of each fuse selectively in contact with the clips.

2. In combination, a base having attaching prongs, spring clips carried by the base, a fuse casing seated by the clips and adapted to be raised and rotated on its axis, fuses insulated from each other in the casing and having contact heads spaced apart circumferentially on the outer face of the casing to contact with said clips, and coacting means carried by the casing and the base for limiting rotation of the casing when seated by the clips to dispose the heads of each fuse selectively in contact with the clips.

3. In a fusible plug, a base having attaching prongs, spring clips carried by the base connected (0' 7 the surface of the casing to contact with said clips, there being depressions formed in the outer face of the casing, and a post on the base engageable in said depressions selectively when the casing is seated by the clips to limit axial rotation of the casing and position the heads of the fuses in sequence in contact with said clips.

4. In a fusible plug, a base having attaching prongs, spring clips carried by the base connected in circuit with the prongs, a cylindrical fuse casing of insulating material seated by the clips and adapted to be raised and rotated on its axis between the clips, said casing being frictionally held at diametrically opposite points by the clips and having an annular series of depressions on its outer face, a partition in said casing dividing the casing into end compartments, fuses on opposite sides of the partition in the compartments having heads exposed on the outer face of the casing and adapted to engage the clips, and a post onthe base between the clips engageable in said depressions selectively when the casing is seated between the clips for limiting rotation of the casing on its axis to dispose the heads of the fuses in contact with the clips.

5. An article of manufacture including a cylindrical casing open at the ends and provided with a cross partition dividing the casing into a compartment at each end, means closing said open ends, and fuses in the compartments terminating in heads exposed on the outer peripheral face of the casing.

6. An article of manufacture including a cylindrical casing open at both ends and having a cross partition dividing the casing into end compartments, the inner wall of the casing being provided with recesses having stop shoulders, means closing the open ends of the casing and having peripheral flanges seated in said recesses and bearing against said shoulders, and fuses in the compartments on opposite sides of the partition having terminal heads exposed on the outer peripheral face of the casing.

7. An article of manufacture including a cylindrical casing having an annular series of depressions disposed on the outer face, a cross partition in the casing dividing the casing into end compartments, transparent windows closing the ends of the casing, and fuses in the compartments on opposite sides of the partition terminating in heads exposed on the outer peripheral face of the casing contiguous to said depressions.

8. A fuse unit including separate fuses, and means insulating said fuses from each other and forming a substantially cylindrical hollow body traversed transversely by said fuses and having the ends of said fuses embedded in the peripheral wall of said body and operatively exposed at the outer circumference thereof.

9. A fuse assembly including a fuse unit, sepa rate fuses, means insulating said fuses from each other and forming a substantially cylindrical body traversed transversely by said fuses and having the ends of said fuses operatively exposed at the periphery thereof, the body being provided with depressions, means seating the unit and providing circuit terminals for coaction with the ends of the fuses selectively when the unit is in set position, and a member selectively engageable in said depressions when the fuse unit is seated by said means for limiting the fuse unit in set position.

ERVIN ADAMS. [L.s.] SAMUEL W. BLAKSLEE. [L.s.] 

